Question

A 75-kilogram bicyclist coasts down a hill at a constant speed of 12 meters per second. What is the kinetic

energy of the bicyclist?
(1) 4.5 × 10^2 J (3) 5.4 × 10^3 J
(2) 9.0 × 10^2 J (4) 1.1 × 10^4 J

Answer 1

Kinetic E=1/2mv^2

KE = 1/2 * 75 * 12^2 = 5400J = 5.4*10^3 J

Answer 2

(3) 5.4 × 10^3 J

Step-by-step explanation:

The kinetic energy of the bicyclist can be calculated using the following equation:

`K=(1)/(2)mv^2`

where

m = 75 kg is the mass of the bicyclist

v = 12 m/s is the speed of the byciclist

By substituting these numbers into the equation, we find:

`K=(1)/(2)mv^2 = (1)/(2)(75 kg)(12 m/s)^2=5400 J=5.4 \cdot 10^3 J`

So, the correct answer is

(3) 5.4 × 10^3 J